//package interfaces;// interfaces/CheckedDowncast.java
//// (c)2021 MindView LLC: see Copyright.txt
//// We make no guarantees that this code is fit for any purpose.
//// Visit http://OnJava8.com for more book information.
//// {NewFeature} Since JDK 17
//
//sealed interface II permits JJ {}
//final class JJ implements II {}
//class Something {}
//
//public class CheckedDowncast {
//  public void f() {
//    II i = new JJ();
//    JJ j = (JJ)i;
//    // Something s = (Something)i;
//    // error: incompatible types: II cannot
//    // be converted to Something
//  }
//}
